World number one women's tennis player Martina Hingis plays her opening match Tuesday against American Lilia Osterloh at the Acura Tennis Classic in San Diego, California.

Sixth seeded Nathalie Tauziat of France, seventh seeded Monica Seles of the United States and Russian star Anna Kournikova join Hingis, the top seed, on the courts. Kournikova is returning to the courts for the first time since suffering a stress fracture in her left foot.

In first round action Monday, American Sandra Cacic defeated Kim-Anh-Nguyen of the United States in straight sets (6-2, 6-3).